Fix live withdraw positions loading

[mircats98gpt]

Summary

• fix usePositions live /api/positions loading by threading the abort signal and retry attempt count through the hook
• expose the stale/offline flags returned by the hook
• remove a duplicate WalletGate import from WithdrawForm

Validation

• git diff --check
• node --experimental-strip-types --check hooks/usePositions.ts

Notes

• The full test suite could not be run locally because dependency installation is still blocked: npm ci reports an out-of-sync npm lockfile and pnpm install --frozen-lockfile --ignore-scripts timed out before test binaries were available.

Fixes #473